[PATCH] buitin-kvm: Update cmd_kvm() to check perf_host value

From: yskelg
Date: Wed May 15 2024 - 15:54:44 EST


From: Yunseong Kim <yskelg@xxxxxxxxx>

According to perf-kvm.txt, the default operation is --guest, meaning
perf_host should be set to false and perf_guest to true. Currently,
the incorrect usage of --no-host and --no-guest still results in
the default --guest operation.

This patch updates the usage messages to include the --no-guest option
for those who only want host data, as well as the --no-host and
--no-guest case.

Signed-off-by: Yunseong Kim <yskelg@xxxxxxxxx>
---
tools/perf/builtin-kvm.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/tools/perf/builtin-kvm.c b/tools/perf/builtin-kvm.c
index 71165036e4ca..654a07658cdd 100644
--- a/tools/perf/builtin-kvm.c
+++ b/tools/perf/builtin-kvm.c
@@ -2129,7 +2129,7 @@ int cmd_kvm(int argc, const char **argv)
OPT_BOOLEAN(0, "guest", &perf_guest,
"Collect guest os data"),
OPT_BOOLEAN(0, "host", &perf_host,
- "Collect host os data"),
+ "Collect host os data. Host only with --host --no-guest"),
OPT_STRING(0, "guestmount", &symbol_conf.guestmount, "directory",
"guest mount directory under which every guest os"
" instance has a subdir"),
@@ -2150,16 +2150,23 @@ int cmd_kvm(int argc, const char **argv)
"buildid-list", "stat", NULL };
const char *kvm_usage[] = { NULL, NULL };

- perf_host = 0;
- perf_guest = 1;
+ /*
+ * tools/perf/Documentation/perf-kvm.txt
+ *
+ * Default('') -> perf.data.guest
+ * --host -> perf.data.kvm
+ * --guest -> perf.data.guest
+ * --host --guest -> perf.data.kvm
+ * --host --no-guest -> perf.data.host
+ */
+ perf_host = false;
+ perf_guest = true;

argc = parse_options_subcommand(argc, argv, kvm_options, kvm_subcommands, kvm_usage,
PARSE_OPT_STOP_AT_NON_OPTION);
- if (!argc)
+ if (!argc || (!perf_host && !perf_guest))
usage_with_options(kvm_usage, kvm_options);

- if (!perf_host)
- perf_guest = 1;

if (!file_name) {
file_name = get_filename_for_perf_kvm();
--
2.34.1